The level of difficulty of a jigsaw puzzle, or picture puzzle, depends generally on three factors: (1) the number of pieces; (2) the shapes of the pieces; (3) the composition of the picture.
Jigsaw puzzles of 1000, 1500, and 2000 pieces are typical. Manufacturers of such puzzles depend primarily on the number of pieces to determine their level of difficulty. Because of limited available surface space, many puzzle doers are unable to use the larger puzzles and must therefore miss the challenge they provide. A typical card table (32".times.32") will conviently hold a 1000 piece puzzle (26".times.20"), both before and after it is assembled. The table will barely hold an assembled 1500 piece puzzle (31".times.23.5"), but there is no space for the loose pieces. A 1500 piece puzzle is therefore not practical on a card table. A 2000 piece puzzle cannot be done on a card table.
This invention dramatically increases the level of difficulty of a jigsaw puzzle, and offers a new challenge, without increasing the size of the puzzle or the number of its pieces. The complexity of a larger puzzle is here made available to the smaller puzzle.